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#include <iostream>
#include <vector>
#include <queue>
#include <algorithm>
#include <string>
#include <set>
#include <unordered_set>
#include <unordered_map>
#include <cmath>
#include <cstdio>
#include <algorithm>
#include <stack>
#include <iomanip>
#include <limits>
#include <cctype>

using namespace std;

int main(int argc, char const *argv[]) {
  std::ios::sync_with_stdio(false);

  int n, a, c = 0;
  cin >> n;
  for(int i = 0; i < n; ++i) {
    cin >> a;
    if(a == 1) {
      ++c;
    }
  }

  if(c == 0) {
    cout << 2 << endl;
  } else if(c == 1) {
    cout << 1 << endl;
  } else {
    cout << 0 << endl;
  }
  cout << 2 << endl;
  cout << 1 << " " << 2 << endl;

  return 0;
}